Including yaru-theme in the in ubuntu-desktop set

[Sebastien Bacher]

Hey there,

Could you include yaru-theme in the ubuntu-desktop exceptions?

Unsure why it's not picked automatically but that was discussed on IRC
with a guessed reason there,
[1] https://irclogs.ubuntu.com/2020/04/17/%23ubuntu-devel.html#t15:09

'gnome-shell needed an exception because it was ending up in
desktop-core for some reason
and yaru-theme-gnome-shell is in gnome-shell-common's Recommends
that script (probably wrongly) doesn't transitively apply its exceptions'

Cheers,
Sebastien Bacher